1. Field of the Invention
The present invention generally relates to a method of recording information on a video disk, such as a LD (Laser Disk), and more particularly to a method of recording TOC (Table-Of-Contents) information in the recording of a MUSE (Multiple Sub-Nyquist Sampling Encoding) signal.
2. Description of Related Art
Recently, there has been considerable activity in the development of high-vision broadcasting suitable for high-definition television broadcasting. In the high-vision broadcasting, the aspect ratio of a picture plane of a television set is as large as 16:9. Further, the number of scanning lines is as many as 1125. Hence, the high-vision broadcasting is capable of transmitting high-definition television signals, and is quite different from the conventional NTSC system.
A high-vision signal is transmitted to users by utilizing a BS (Broadcasting Satellite). Usually, the high-vision signal needs a transmission band approximately equal to or larger than five times the transmission bands of the existing television broadcasting systems. Hence, if the high-vision signal is transmitted without any processing, it is impossible to transmit the high-vision signal within a band width equal to one channel of the BS.
In order to transmit the high-vision signal within a band width equal to one channel of the BS, a MUSE system has been developed, as disclosed in "DEVELOPMENT OF MUSE SYSTEM", NHK (Japan Broadcasting Association) Technical Study, Vol. 39, No. 2, Ser. No. 172, 1987, or "HIGH-VISION SATELLITE TRANSMISSION SYSTEM-MUSE", The Journal of the Institute of Television Engineers of Japan, Vol. 42, No. 5, 1988. In the MUSE system, the high-vision signal is processed by multiple sub-sampling so that it is compressed in a transmission band of 8.1MHz and transferred in analog form. A band compressed signal is called as a "MUSE signal".
The above is an outline of the high-vision broadcasting and MUSE system. It is possible to apply the above technique to the recording or reproducing of video signals for video disks, such as laser disks, as in the case of the conventional NTSC system. That is, analog MUSE signals are recorded on video disks.
According to the present inventor's research in the application of this MUSE signal to the video disk recording, it can be seen from the transmission signal format of the MUSE signal that the MUSE system has an undefined line, which is a line having a horizontal scanning period number (hereinafter, referred to as a line number) "564" in case that the MUSE system is applied to the video disk recording. Namely, in the broadcasting system, the undefined line is used as a program transmission control signal, while this is not needed in a non-broadcasting system. That is, the No. 564 line is a "free" line in the video disk recording.
Accordingly, the inventors of the present invention have found that it is possible to improve operationability and functionability of video disk players by inserting predetermined data into this free line having the line number 564. The predetermined data is, for example, data for controlling a video disk player, and data for reproduction control, such as address data related to information recorded on a video disk. Hereinafter, the predetermined data as described above is referred to as a disk code DSCD.
At present, there is no united or specified standard concerning the disk code DSCD for the No. 564 line recorded on the video disk, according to the related arts.
Meanwhile, in the NTSC system, table-of-contents information (hereinafter simply referred to as TOC data or information) concerning the address of information recorded on the video disk is not recorded thereon. In a random access operation on the video disk in conformity with the NTSC system, desired information is searched for using a frame number inserted into a program area, or using a chapter number inserted therein if the chapter number is recorded on the video disk, which requires rather complicated system structure and in which the search can be enabled rather slowly.